Hex与Double类型之间的转换

来源：互联网发布：sam 软件编辑：程序博客网时间：2024/05/21 09:49

unsigned int getbitu(const unsigned char *buff, int pos, int len)
{

unsigned int bits=0;int i;for (i=pos;i<pos+len;i++){    bits=(bits<<1)+((buff[i/8]>>(7-i%8))&1u);}return bits;

}

/将十六进制的数转换成double型/
double HexToDouble(const unsigned char* buf)
{

double value = 0;unsigned int i = 0;unsigned int num,temp;int num2;bool flags1 = false;bool flags2 = false;num = getbitu(buf,i,1);             i += 1;num2 = getbitu(buf,i,11) - 1023;    i += 11;if(num2 >= 0){    flags2 = true;    while(1)    {        flags1 = true;        if(flags2)        {            flags2 = false;            value += 1 * pow(2,num2); num2--;        }        temp = getbitu(buf,i,1);    i += 1;        value += temp * pow(2,num2); num2--;        if(num2 < 0 || i == 64);            break;    }}while(1){    if(flags1)    {        temp = getbitu(buf,i,1);    i += 1;        value += temp * pow(2,num2); num2--;    }    else    {        flags1 = true;        value += 1 * pow(2,num2); num2--;    }    if(i == 64)        break;}if(num == 1)    value *= -1;return value;

}

/将double型数据转换成十六进制表示/
void DoubleToHex(double m,unsigned char* buf)
{

int i;int m1;//double型数据的整数部分double m2,m3;//double型数据的小数部分int num1;//阶数的值int num2;//尾数的位数long long int temp1 = 0;long long int temp2 = 0;//符号位判断if(m >= 0){    buf[0] = 0;}else{    buf[0] = 128;}m = fabs(m);//将double型数分解成整数部分和小数部分m1 = floor(m);m2 = m - m1;//阶数计算if(m1 > 0){    for(num1 = 0,temp1 = 1; 2*temp1 <= m1; num1++)    {        temp1 *= 2;    }    num1 += 1023;}else{    for(num1 = 0, m3 = m2; m3 <= 1; num1++)    {        m3 *= 2;    }    num1 = 1023 - num1;}buf[0] += ((num1 >> 4) & 0x0ff);buf[1] = (num1 & 0x0f) << 4;//尾数计算if(m1 > 0){    for(num1 = 0; m1/2 > 0; num1++)    {        temp1 = (temp1 << 1) + m1%2;        m1 = m1/2;    }    for(i = 0; i < num1; i++)    {        temp2 = (temp2 << 1) + (temp1 & (0x01));        temp1 = temp1 >> 1;    }    for(i = 0; i < 52 - num1; i++)    {        temp2 = (temp2 << 1) + floor(m2*2);        m2 = m2*2 - floor(m2*2);    }   }else{    do    {        m2 *= 2;    }while(m2 < 1);    m2 -= floor(m2);    for(i = 0; i < 52; i++)    {        temp2 = (temp2 << 1) + floor(m2*2);        m2 = m2*2 - floor(m2*2);    }}//将转换后的数据存放到数组中for(i = 7; i > 1; i--){    buf[i] = temp2 & 0x0ff;    temp2 = temp2 >> 8;}buf[1] += temp2 & 0x0f;

}

0 0